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51.
The effect of the hydrothermal treatment with aqueous NaOH solution on the photoelectrochemical and photocatalytic properties of visible light-responsive TiO2 thin films prepared on Ti foil substrate (Vis-TiO2/Ti) by a radio-frequency magnetron sputtering (RF-MS) deposition method has been investigated. The hydrothermally treated Vis-TiO2/Ti electrodes exhibited a significant increase in their photocurrent under UV and visible light irradiation as compared to untreated Vis-TiO2/Ti electrode. SEM investigations revealed that the surface morphology of Vis-TiO2/Ti are drastically changed from the assembly of the TiO2 crystallites to the stacking of nanowires with diameters of 30–50 nm with increasing hydrothermal treatment time (3–24 h), accompanying the increase in their surface area. The separate evolution of H2 and O2 from water under solar light irradiation was successfully achieved using the Vis-TiO2/Ti/Pt which is hydrothermally treated for 5 h, while the H2 evolution ratio was 15 μmol h−1 in the early initial stage, corresponding to a solar energy conversion efficiency of 0.23%.  相似文献   
52.
An experimental study was conducted in search of the experimental condition required for the much needed suppression of spectral interference caused by surface water in hydrogen analysis using laser-induced low-pressure helium plasma spectroscopy. The problem arising from the difficulty in distinguishing hydrogen emission from hydrogen impurity inside the sample and that coming from the water molecules was overcome by taking advantage of similar emission characteristics shared by hydrogen and deuterium demonstrated in this experiment by the distinct time-dependent and pressure-dependent variations of the D and H emission intensities from the D-doped zircaloy-4 samples. This similarity allows the study of H impurity emission in terms of D emission from the D-doped samples and thereby separating it from the H emission originating from the water molecules. Employing this strategy has allowed us to achieve the large suppression of water induced spectral interference from the previous minimum of 400 microg/g to the current value of 30 microg/g when a laser beam of 34 mJ under tight focusing condition was employed. Along with this favorable result, this experimental condition has also provided a much better (about 6-fold higher) spatial resolution, although these results were achieved at the expense of reducing the linear calibration range from the previous 4 300 microg/g to the present 200 microg/g.  相似文献   
53.
The present study investigated the effects of touch button size on touchscreen operability and compared these effects between young adult and elderly participants. A total of 21 young adults (aged 22.3 ± 1.5 years) and 20 elderly adults (aged 68.1 ±4.9 years) were recruited and asked to press square number buttons (from 0 to 9) on an experimental touchscreen with their right index finger. The buttons' size changed during the experiment with six conditions (6, 8, 10, 12, 14 and 16 mm). It was found that a decrease of the button size to l0 mm or below tended to increase the operation time and error rate, whereas it decreased the subjective overall operability of the touchscreen. Such effects were greater in the elderly adults than in the young adults. In addition, the reaction positions on the buttons were found to be close to the right side of them, which led the fingertip to approach the right outline of the buttons. These findings suggest that the use of small touch buttons should be minimised on touchscreens, especially for elderly users.  相似文献   
54.
55.
Kolesnikov  Sergey  Fukumoto  Eriko  Bozeman  Barry 《Scientometrics》2018,116(3):1995-2017
Scientometrics - In the quest for balance between research productivity and impact, researchers in science and engineering are often encouraged to adopt a play-it-safe research and publication...  相似文献   
56.
In order to evaluate antimicrobial activity of ciprofloxacin (CPFX), minimum inhibitory concentrations (MICs) of CPFX and other drugs were determined against clinical isolates that were obtained in our laboratory from January to December of 1991, and of 1993. The results are summarized as follows: 1. CPFX-resistant strains were on the increase in various strains, compared to those in the early 1980s. However, many of CPFX-resistant strains were multi-drug resistant including beta-lactams. In addition, they showed cross resistance to other fluoroquinolone agents. 2. MIC distribution of other drugs suggested that there were increased frequencies of benzylpenicillin (PCG)-insensitive Streptococcus pneumoniae (PISP) and CEPs-resistant Escherichia coli. However, MIC distribution of CPFX to these resistant strains were in a relatively low range. 3. When isolates of 1991 were compared to those of 1993, we confirmed that CPFX-resistant strains decreased among certain bacteria such as Staphylococcus aureus. Also we confirmed that fewer CPFX-resistant strains were found among bacteria that may be highly related to infections encountered in daily medical care.  相似文献   
57.
We describe a female patient with primary Sj?gren's syndrome who subsequently developed chronic myelogenous leukemia. The patient received a bone marrow transplant (BMT) from a genotypically HLA-identical brother after pre-transplant preparation with busulfan and cyclophosphamide. Eighteen weeks later, cutaneous and mucosal chronic graft-versus-host disease developed, followed by death 11 months after transplantation. Anti-Ro/SS-A antibodies disappeared within 6 months post-BMT, but antinuclear antibodies remained positive through the post-transplant course.  相似文献   
58.
BACKGROUND: Treatment options for malignant gastric outlet obstruction are limited. Surgical gastrojejunostomy, commonly performed, has significant morbidity and mortality. METHODS: Over 2 years, we prospectively studied the safety, feasibility, and outcomes for use of a newly designed expandable metal stent (Wallstent Enteral; Schneider, Minneapolis, Minn.) to treat malignant gastric outlet obstruction. Stents 16 to 22 mm in diameter and 60 to 90 mm in length were deployed directly through the endoscope. RESULTS: Twelve patients (ten women, two men; mean age 59.7 years) underwent stenting. Thereafter, six patients were able to eat a regular diet; three could eat pureed food. In three patients, the procedure was unsuccessful because of multiple obstructions not recognized before stenting (one) and stents deployed too proximally (one) or too distally (one). CONCLUSIONS: Placement of a newly designed stent through the endoscope is safe and effective palliation for various types of malignant gastric outlet obstruction and significantly improves many aspects of patient quality of life.  相似文献   
59.
The Children Act focuses attention on meeting the assessed needs of children with disabilities. General practitioners (GPs) and Community Child Health (CCH) doctors in one health district were asked by postal questionnaire who it was who currently assessed such needs and who would do so in the future. The involvement of GPs (15) varied from none (1) to regular reassessment (3). Nearly all (14) treated acute illnesses but educational assessments were assigned to CCH doctors. Community doctors (9) had a clearer idea of their role including regular reassessment (9), education assessment (9) and interagency liaison (3). Both groups complained of poor communication with each other and with hospital services. To fulfil the requirements of the Children Act, community child health services, family health services authorities and district health authorities will have to specify how and by whom children with disabilities are identified and assessed. Arrangements will vary according to local service development. These arrangements, and the resulting liaison with other agencies, should be specified in National Health Service contracts, thus improving communication and cooperation.  相似文献   
60.
The HIT-CTI mark II compact toroid (CT) injector employed for the JFT-2M tokamak facility at the Japan Atomic Energy Research Institute (JAERI) has been upgraded to improve injection performance. The nozzle of the mark III injector now has a linear tube in place of the original focus cone to avoid rapid focus and deceleration, and the tapered outer electrode has been replaced with more gentle taper in the compression section in order to facilitate gradual compression. The dependence of CT velocity and electron density on poloidal bias flux and trigger time of CT acceleration have been investigated in the operable range of 70–230 km/s average CT velocity and electron density of 0.1–1.0 × 1022 m−3 at an accelerator bank voltage of 25 kV. The operation window is broader than that of the mark II injector. Emission of a CT plasmoid from the injector, and transport to the flux conserver as a high-density spheromak magnetic structure have also been confirmed.  相似文献   
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